How thick under pad for Flatwater Freestyle?

[JGringo]

I ended up doing some surgery after trying my current set-up just in the shop. I am SO GLAD that I did. My foot positioning to way better, and my foot is never coming out... This is probably a bad thing, but it was more the idea I had originally thought for these holds... I know people are going to roast me for this, but I threw some sexwax onto the turf to add a little grip. When I just barely have my toes in, I have complete control and my foot won't pull out easily. Now I can position my body how I want more easily without worrying if my entire foot is in the hold.

Thanks Matt and others for the input!
-Gringo